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Calcium metabolism is normal
The normal daily intake of calcium is 600-800 mg. Absorption occurs mainly in the proximal part of the small intestine. In the intestine, calcium secretion is also carried out, the rate of which is constant and does not depend on absorption. Typically, up to 80% of the calcium consumed is excreted in the feces.
Calcium excretion is via the kidneys, averaging 100 mg / day, and can range from 50 to> 300 mg / day. Normally, 98% of the calcium filtered in the renal glomeruli is reabsorbed. Reabsorption of calcium (like sodium) occurs in the proximal tubules and in the ascending part of the Henle loop. In the distal tubules, calcium reabsorption depends on the secretion of parathyroid hormone (PTH), while sodium reabsorption depends on the secretion of aldosterone. An increase in the concentration of PTH in the blood increases the reabsorption of calcium in the distal tubules and reduces its excretion by the kidneys.
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Calcium metabolism is normal
- Potassium metabolism is normal
Normally, an adult consumes an average of 80 meq of potassium per day (from 40 to 140 meq). About 70 meq of potassium is excreted in the urine, 10 meq - through the gastrointestinal tract. Renal excretion of potassium ranges from 5 meq / l to 100 meq / l. Almost all potassium filtered by the renal glomeruli is reabsorbed in the proximal tubules and the Henle loop. The excretion of potassium in the urine occurs due to
- Water exchange is normal
An adult consumes approximately 2500 ml of water per day, including approximately 300 ml of water resulting from metabolism. Water loss is about 2500 ml / day, of which 1500 ml is excreted in the urine, 800 ml is evaporated (400 ml through the respiratory tract and 400 ml through the skin), 100 ml is excreted with sweat and another 100 ml with feces. Evaporation water loss plays a very important role in
- EXCHANGE OF CALCIUM, PHOSPHORUS AND BONE TISSUE: CALCIUM REGULATING HORMONES
Michael F. Holik, Stefep M. Krepi, Joey T. Potts, Jr. (Michael F. Holick, Stephen M. Krone, John T. Potts, Jr.) The structure and metabolism of bone tissue (see chap. 337) Bone is dynamic tissue, constantly changing over the course of a person’s life. Skeleton bones are well vascularized and receive approximately 10% of the minute volume of blood. The structure of dense and cancellous bones
- Sodium metabolism is normal
An adult consumes an average of 170 meq of sodium per day (Ir sodium contains 43 meq of sodium ions, while 1 g of NaCl contains 17 meq of sodium ions). There are renal and extrarenal sodium excretion routes. The leading role in the regulation of sodium metabolism is played by the kidneys, which are able to change its concentration in the urine from 1 meq / l to> 100 meq / l (Ch.
- Normal phosphorus metabolism
An adult consumes an average of 800-1500 mg of phosphorus per day. About 80% of this amount is absorbed in the proximal small intestine, and vitamin D stimulates the absorption of phosphorus in the intestine. Phosphorus excretion is carried out mainly through the kidneys, which are the main regulator of the total phosphorus content in the body. Renal excretion of phosphorus depends both on its
- Metabolism of magnesium is normal
Adult magnesium intake on average is 20-30 meq / day (240-370 mg / day). Only 30-40% of this amount is absorbed, mainly in the distal small intestine. Magnesium excretion is mainly carried out by the kidneys and averages 6-12 meq / day. Reabsorption of magnesium in the kidneys is extremely effective: 25% of the magnesium filtered in the renal glomeruli undergoes
- Plasma Calcium Concentration
Normally, the plasma calcium concentration is 8.5-10.5 mg / 100 ml (2.1-2.6 mmol / L). About 50% of plasma calcium is in free ionized form, 40% is associated with proteins (mainly with albumin) and 10% - with anions (with citrate and amino acids). Physiologically active is free ionized calcium, the concentration of which ([Ca2 +]) is most
Calcium function is necessary for the structural integrity and mineralization of bones and teeth and plays an important role in a number of metabolic and regulatory processes. It is a concomitant factor of many enzymes necessary for the functioning of the nervous and muscular systems, a component of the blood coagulation system, and a regulator of many intracellular processes. Adequate intake of calcium is vital
- Imbalance in calcium
Calcium plays a paramount role in the metabolic and many physiological processes of the human body. It is the main building block of bones. Calcium ions play an important role in the transmission of intracellular signals, various enzyme reactions, and blood coagulation. Calcium determines neuromuscular conduction. Regulation of calcium balance stabilization is a process of great importance. 99%
It is the most common mineral substance in the human body. Calcium not only plays a crucial role in the formation of inert tissue, but also is part of the blood, cell and tissue fluids. This microelement directly affects the processes of muscle contraction, and, therefore, all human motor activity depends on it. It also affects the stimulation of several functions.
- Calcium metabolic disorders
Calcium is found mainly in bones (98%), but maintaining its normal extracellular concentration is extremely important. Calcium ions are involved in almost all physiological processes, including muscle contraction, the release of neurotransmitters and hormones, blood coagulation, and bone metabolism. Therefore, calcium metabolism disorders can lead to severe disorders of many
- CALCIUM PHOSPHATE CRYSTALLURIA
It was found that when calcium phosphate precipitates from a highly saturated aqueous solution at a pH of more than 7, amorphous phosphates first appear. An amorphous precipitate can slowly transform into a stable crystalline precipitate due to the process of dissolution, renucleation and crystal growth. Transformation rate is pH dependent. The stability of amorphous phosphates improves at high pH.
- CALCIUM OXALATE CRYSTALLURIA
Features Calcium crystals of oxalate dehydrate are usually colorless, with a characteristic octohedral or oval shape (Fig. 4-11). Under a light microscope, they look like large or small squares, the corners of which are connected by diagonal lines. Calcium oxalate crystals are found in acidic, neutral, or alkaline urine. Calcium oxalate monohydrate crystals vary in size and can
- Regulation of extracellular concentration of ionized calcium
The entry of calcium into the extracellular fluid occurs either upon absorption from the intestine, or as a result of resorption from bone tissue; no more than 0.5-1% of bone calcium is involved in the exchange with extracellular fluid. Calcium can leave the extracellular space due to: 1) deposition in bones; 2) urinary excretion; 3) secretion in the digestive tract and 4) excretion with sweat. Extracellular concentration
- CALCIUM CARBONATE CRYSTALLURIA
Calcium carbonate can crystallize in the urine of horses, rabbits, goats, forming large yellow-brown or colorless spheroids with radial striation, or small crystals of round, oval or dumbbell-shaped (Fig. 2 and 3). In dogs and cats, these crystals are usually not found. If a dumbbell-shaped crystal is found in the urine, then it is rather calcium oxalate monohydrate. Fig.
- CALCIUM CARBIDE (CALCIUM CARBIDE)
GENERAL INFORMATION Empirical formula. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CaC2 Molecular weight, kg / kmol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64.1 Aggregate state. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Solid Appearance. . . . . . . . . . . . . . .
- Calcium deficiency in a child
Sometimes, with breast milk, the baby does not get enough calcium, even with a sufficient amount of it in the mother’s diet, due to a violation of calcium metabolism in her body. A lack of calcium and a disorder, in turn, of calcium metabolism in a baby is fraught for him with impaired development of the skeletal system and teeth, often accompanied by anemia, susceptibility to colds, infections and allergic reactions.